COGNITIVE DISORDERS

Andrzej Kokoszka

COGNITIVE DISORDERS

Cognitive disorders (formerly called organic mental syndromes) involve problems in memory, orientation, level of consciousness, and other cognitive functions.

• a. These difficulties are due to abnormalities in neural chemistry, structure, or physiology originating in the brain, or secondary to systemic illness.

• b. Patients with cognitive disorders may show psychiatric symptoms secondary to the cognitive problems (e.g., depression, anxiety, paranoia, hallucinations, and delusions).

• c. The major cognitive disorders are delirium, dementia, and amnestic disorder.

General information

COGNITIVE DISORDERS

General information

COGNITIVE DISORDERS

General information

Delirium Due to General Medical Condition …

include the name of the general medical condition A. Disturbance of consciousness (i.e., reduced clarity of

awareness of the environment) with reduced ability to focus, sustain, or shift attention.

B. A change in cognition (such as memory deficit, disorientation, language disturbance) or the development of a perceptual disturbance that is not better accounted for by a preexisting, established, or evolving dementia.

C. The disturbance develops over a short period of time (usually hours to days) and tends to fluctuate during the course of the day.

D. There is evidence from the history, physical examination, or laboratory findings that the disturbance is caused by the direct physiological consequences of a general medical condition

General information

DEMENTIA

A. Demonstrable evidence of impairment in short- and long-term memory. Impairment in short-term memory (inability to learn new information) may be indicated by inability to remember three objects after five minutes. Long-term memory impairment (inability to remember information that was known in the past) may be indicated by inability to remember past personal information

• (e.g., what happened yesterday, birthplace, occupation) or facts of common knowledge (e.g., past Presidents, well-known dates).

B At least one of the following:• (1) impairment in abstract thinking, as indicated by inability to find similarities and

differences between related words, difficulty in defining words and concepts, and other similar tasks

• (2) impaired judgment, as indicated by inability to make reasonable plans to deal with interpersonal, family, and job-related problems and issues

• (3) other disturbances of higher cortical function, such as aphasia (disorder of language), apraxia (inability to carry out motor activities despite intact comprehension and motor function), agnosia (failure to recognize or identify objects despite intact sensory function), and "constructional difficulty" (e.g., inability to copy three-dimensional figures, assemble blocks, or arrange sticks in specific designs)

• (4) personality change (i.e., alteration or accentuation of premorbid trans)

DSM-III-R

DEMENTIA

C. The disturbance in A and B significantly interferes with work or usual social activities or relationships with others. D Not occurring exclusively during the course ot delirium.

E. Either (1) or (2):• (1) there is evidence from the history, physical

examination, or laboratory tests of a specific organic factor (or factors judged to be etiologically related to the disturbance

• (2) in the absence of such evidence, an etiologic organic factor can be presumed if the disturbance cannot be accounted for by any nonorganic mental disorder (e.g., major depression accounting for cognitive impairment)

DSM-III-R

DEMENTIA

Criteria for severity of Dementia:• Mild: Although work or social activities are

significantly impaired, the capacity for independent living remains, with adequate personal hygiene and relatively intact judgment.

• Moderate: Independent living is hazardous, and some degree of supervision is necessary.

• Severe: Activities of daily living are so impaired that continual supervision is required (e.g., unable to maintain minimal personal hygiene; largely incoherent or mute).

DSM-III-R

DEMENTIA

Once dementia has been di agnosed on clinical grounds (with or without the aid of neuropsychological tests), a determination of its cause and the possibility of treatment should be made

• About 10 percent of dementias are treatable. Most cases, however, are progressive and incurable.

• The onset of dementia may be sudden, resulting from head trauma, cardiac arrest with cerebral hypoxia, or encephalitis.

• More often, however, the onset is insidious, as in primary degenerative dementia of the Alzheimer type, cerebrovascular disease, and hypothyroidism.

• Dementia resulting from brain tumors, subdural hematomas, and metabolic disorders may also have an insidious onset.

General information

Diseases that cause dementia

• Parenchymatous diseases of the central nervous system • Alzheimer's disease (primary degenerative dementia) • Pick's disease (primary degenerative dementia) • Huntington's disease• Parkinson's disease*• Multiple sclerosis • Systemic disorders• Endocrine and metabolic disorders • Thyroid disease*• Parathyroid disease*• Pituitary-adrenal disorders*• Posthypoglycemic states

*Reversible conditions calling for specific therapeutic interventions

intervention.

Diseases that cause dementia

• Liver disease• Chronic progressive hepatic encephalopathy*• Urinary tract disease• Chronic uremic encephalopathy*• Progressive uremic encephalopathy (dialysis dementia) * • Cardiovascular disease• Cerebral hypoxia or anoxia*• Multi-infarct dementia*• Cardiac arrhythmias*• Inflammatory diseases of blood vessels*• Pulmonary disease• Respiratory encephalopathy*

*Reversible conditions calling for specific therapeutic interventions

intervention.

Diseases that cause dementiaDeficiency states• Cyanocobalamin deficiency*• Folic acid deficiency*• Drugs and toxins*• Intracranial tumors* and brain trauma*• Infectious processes • Creutzfeldt-Jakob disease • Cryptococcal meningitis* • Neurosyphilis*• TB and fungal meningitis*• Viral encephalitis• Human immunodeficiency virus (HIV)-related disorders (e g. AIDS and AIDS-related

complex [ARC]) • Miscellaneous disorders• Hepatolenticular degeneration*• Hydrocephalic dementia*• Sarcoidosis*• Normal pressure hydrocephalus*

*Reversible conditions calling for specific therapeutic interventions

intervention.

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE)

• Is the most common type of dementia (50-65%) of all dementias, and is diagnosed when other obvious causes for the symptoms have been eliminated.

• Patients show a gradual loss of memory and intellectual abilities, inability to control impulses, and lack of judgment. Depression and anxiety often are seen.

• Later in the illness, symptoms include confusion and psychosis that progress to coma and death (usually within 8-10 years of diagnosis).

• For patient management and prognosis, it is important to make the distinction between Alzheimer disease and both pseudodementia (depression that mimics dementia) and normal aging.

General information

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE)

Genetic associations in Alzheimer disease include• Abnormalities of chromosome 21 (Down syndrome

patients ultimately develop Alzheimer disease).• Abnormalities of chromosomes 1 and 14 implicated

particularly in early onset Alzheimer disease (i.e., occurring before age 65).

• Possession of at least one copy of the apolipoprotein E4 (apoE4) gene on chromosome 19.

• Gender - there is a higher occurrence of Alzheimer disease in women. 3.

General information

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE) Genetic associations in Alzheimer disease include• Abnormalities of chromosome 21 (Down syndrome

patients ultimately develop Alzheimer disease).• Abnormalities of chromosomes 1 and 14 implicated

particularly in early onset Alzheimer disease (i.e., occurring before age 65).

• Possession of at least one copy of the apolipoprotein E4 (apoE4) gene on chromosome 19.

• Gender - there is a higher occurrence of Alzheimner disease in women. 3.

General information

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE) Neurophysiological factors• a. Decreased activity of acetylcholine (ACh) and reduced

brain levels of choline acetyl transferase (i.e., the enzyme needed to synthesize ACh).

• b. Abnormal processing of amyloid precursor protein.• c. Overstimulation of the N-methyl-D-aspartate (NMDA)

receptor by glutamate.

Gross anatomical changes occur in Alzheimer disease.• a. Brain ventricles become enlarged.• b. Diffuse atrophy and flattened sulci appear.

General information

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE) Microscopic anatomical changes occur in

Alzheimer disease.• Senile (amyloid) plaques and neurofibrillary

tangles are seen (seen also in Down syn drome and, to a lesser extent, in normal aging).

• Loss of cholinergic neurons occurs in the basal forebrain.

• Neuronal loss and degeneration are seen in the hippocampus and cortex.

General information

DEMENTIA OF ALZHEIMER’S TYPE (ALZHEIMER DISEASE)

• Has a progressive, irreversible, downhill course.• The most effective initial interventions involve providing a

structured environment including visual-orienting cues. Such cues include:- labels over the doors of rooms identifying their function; - daily posting of the day of the week, date, and year; - daily written activity schedules; - and practical safety measures (e.g., disconnecting the stove).

General information

COGNITIVE DISORDERS

General information

DEMENTIA OF ALZHEIMER’S TYPE

(ALZHEIMER DISEASE)

Pharmacologic interventions include:• Acetylcholinesterase inhibitors [e.g., tacrine (Cognex),

donepezil (Aricept), rivastig mine (Exelon), and galantamine (Reminyl)j to temporarily slow progression of the dis ease. These agents cannot restore function already lost.

• Memantine (Namenda), an NMDA antagonist, was recently approved to slow deterioration in patients with moderate to severe disease.

• Psychotropic agents are used to treat associated symptoms of anxiety, depression, or psychosis.

General information